Defense Secretary Donald Rumsfeld flew to the Horn of Africa Tuesday, his stated purpose to thank countries there for their cooperation in the war on terrorism. Mr. Rumsfeld says his visits to Eritrea, Ethiopia and Djibouti are not designed, in his words, to engage in transactions or to put pressure on anybody.

Instead, speaking to reporters on board his plane en route to the Horn, Mr. Rumsfeld says he is making his first-ever trip to the region to demonstrate the fact that the United States values the assistance it is receiving from all three countries. He says that assistance in the war on terrorism has included the sharing of intelligence, maritime cooperation, overflight permission and access to military bases.

For the moment U.S. air, naval and ground forces are making extensive use of facilities in only one of the three Horn countries, Djibouti. But Mr. Rumsfeld is leaving open the possibility of an expansion of the American presence, saying there are ongoing discussions regarding possible use of military facilities in Ethiopia and Eritrea.

Mr. Rumsfeld gives no details. The United States has previously had a military presence in Eritrea. After World War II, it established a naval repair base at the port of Massawa and an intelligence post in Asmara. However these have both been closed for years. And diplomatic sources have said plans to develop a new military relationship have been blocked by the detention of two Eritreans who worked for the U.S. Embassy in Asmara. The two were arrested late last year after the United States issued a statement criticizing Eritrea's government for cracking down on political dissent.

Still, Mr. Rumsfeld says the cooperation of countries of all sizes worldwide is absolutely essential if the effort to track down terrorist cells is to be successful. And he says there are al-Qaida in the Horn of Africa region.